Volume 26, Number 8—August 2020
Dispatch
Evolution and Antigenic Drift of Influenza A (H7N9) Viruses, China, 2017–2019
Table 1
Antigen | Antiserum, titer |
|||||||
---|---|---|---|---|---|---|---|---|
H7N9-Re-2† | H7N9-rGD76† | 181115 | H7SD12 | H71903‡ | LN19010 | 19225 | 19294 | |
H7N9-Re-2 | 1,024 | 2,048 | 256 | 512 | 512 | 1,024 | 1,024 | 2,048 |
H7N9-rGD76 | 128 | 1,024 | 128 | 512 | 256 | 256 | 256 | 128 |
181115 | 64 | 256 | 1,024 | 256 | 256 | 256 | 128 | 128 |
H7SD12 | 64 | 256 | 256 | 1,024 | 1,024 | 2048 | 1,024 | 1,024 |
H71903 | 64 | 512 | 256 | 1,024 | 1,024 | 1,024 | 2048 | 1,024 |
LN19010 | 32 | 256 | 32 | 512 | 512 | 512 | 512 | 512 |
19225 | 32 | 256 | 64 | 1,024 | 512 | 1,024 | 512 | 1,024 |
19294 | 32 | 256 | 64 | 512 | 512 | 1,024 | 512 | 512 |
19300–1 | 32 | 256 | 64 | 1,024 | 512 | 1,024 | 512 | 512 |
19743 | 16 | 64 | 16 | 512 | 256 | 256 | 256 | 128 |
19797 | 16 | 32 | 16 | 256 | 128 | 128 | 64 | 128 |
19854–2 | 16 | 64 | 16 | 512 | 256 | 256 | 256 | 256 |
19854–6 | 16 | 64 | 16 | 256 | 256 | 512 | 256 | 256 |
LN191012 | 16 | 64 | 16 | 512 | 256 | 256 | 128 | 128 |
AH191005 | 32 | 128 | 32 | 1,024 | 512 | 256 | 256 | 256 |
*181115, A/chicken/northeast China/181115/2018(H7N9); H7SD12, A/chicken/east China/H7SD12/2019(H7N9); HeB1908, A/chicken/north China/HeB1908/2019(H7N9); LN19010, A/chicken/northeast China/LN19010/2019(H7N9); 19225, A/chicken/northeast China/19225/2019(H7N9); 19294, A/chicken/northeast China/19294/2019(H7N9); 19300–1, A/chicken/northeast China/19300–1/2019(H7N9); 19743, A/chicken/northeast China/19743/2019(H7N9); 19797, A/chicken/northeast China/197971/2019(H7N9); 19854–2, A/chicken/northeast China/19854–2/2019(H7N9); 19854–6, A/chicken/northeast China/19854–6/2019(H7N9); LN19010, A/chicken/northeast China/LN19010/2019(H7N9); LN191012, A/chicken/northeast China/LN191012/2019(H7N9); AH191005, A/chicken/east China/AH191005/2019(H7N9).
†H7N9-Re-2 and H7N9-rGD76 are vaccine strains widely used in China; both antigen and antiserum of H7N9-Re-2 were purchased from the Harbin Weike Biotechnology Development Company (www.hvriwk.com), the antigen of H7N9-Re-2 was available from reassortant avian influenza virus trivalent vaccine. The antigen and antiserum of H7N9-rGD76 were available from Guangzhou South China Biologic Medicine (http://www.gzscbm.com).
‡H71903 is candidate vaccine strain containing the hemagglutinin and neuraminidase genes from H7SD12 and 6 internal genes from A/duck/Guangdong/D7/2007(H5N2). H7SD12, 181115, HeB1908, LN19010, 19225, 19294, 19300–1, 19743, 19797, 19854–2, 19854–6, LN19010, LN191012, and AH191005 are highly pathogenic H7N9 strains in this study.
1These authors contributed equally to this article.